The present invention is related to a fan guard for guiding an airflow, and particularly to a fan guard for guiding an airflow to dissipate heat generated from an electronic device.
As time goes by, the electronic devices are further miniaturized and the circuits are designed to further increase density for improvement of speed, performance, and power efficiency. However, this trend arises several problems. One of the problems is the heat generated from the electronic devices, which will shorten the useful lifetime of the electronic devices. At the present time, the heat removal from the electronic devices for allowing the electronic devices to perform normally has attracted great attention.
Generally, three different ways are adopted to solve the problem of heat generated from the electronic devices.
(1) Focusing on the design of circuits.
Though it""s possible to design simpler electronic circuits, it""s really hard to look after both the problem of heat and the performance of electronic devices.
(2) Focusing on the design of radiator plate.
At the present time, the radiator plates are generally made of aluminum. For solving the problem of heat generated from the electronic devices, a variety of the radiator plates may be formed possibly by a way of injection molding of aluminum. As we know, a radiator plate with more surface area may solve the problem of heat generated from the electronic devices. Unfortunately, there is no longer any space for advancement in the design of radiator plate. In addition, it will take a longer time to develop a new material for replacing aluminum to solve the above-described problem.
(3) Focusing on the design of the fan assembly.
Most researchers focus on the design of the motor of the fan assembly for improving the heat-dissipating efficiency.
Please refer to FIG. 1 showing a combination of the conventional fan assembly, the radiator plate and the electronic device. The conventional fan assembly includes a fan 17 and a fan guard 13. The fan further includes a stator 11, a rotor 12 and a plurality of blades 121 which are disposed on the rotor 12 for generating an airflow by revolution. The airflow flows into the fan assembly from the airflow inlet of the fan assembly 151 and out from the airflow outlet of the fan assembly 152 to the radiator plate 14. Thereafter, the airflow passes through the gap of the radiator plate 141 to lower its temperature. Because the electronic device 16 is contacted with the radiator plate 14, the heat generated from the electronic device 16 is transferred to the radiator plate 14 and dissipated by the airflow from the airflow outlet 152 of the fan assembly. Alternatively, the airflow out from the airflow outlet of the fan assembly 152 can flow directly onto the electronic device 16 through the gap of the radiator plate 141.
The electronic circuit is generally disposed on a central surface of an electronic device. However, for the conventional fan assembly, the diameters of the airflow outlet and inlet of the fan assembly for passing through an airflow are the same so that the airflow out from the airflow outlet of the fan assembly 152 is not easy to directly flow toward the central surface of the electronic devices. Therefore, the heat-dissipating efficiency of the conventional fan assembly is limited.
In addition, the stator of the conventional fan assembly directly contacts on the surface of the radiator plate 14, thereby blocking the airflow out from the airflow outlet of the fan assembly 152 from directly flowing onto the central surface of the electronic devices. Therefore, it is desirable to solve the problem encountered by the prior arts, that is, the heat-dissipating problem of the electronic devices.
An object of the present invention is to provide a fan guard for guiding an airflow toward the central surface of the electronic devices to effectively dissipate heat generated from the electronic devices.
Another object of the present invention is to provide a fan assembly for guiding airflow toward the central surface of the electronic devices to improve the speed, performance, and power efficiency and to elongate the useful lifetime of the electronic devices.
The fan assembly comprises a fan for generating airflow by revolution and a fan guard, wherein the fan guard has an airflow inlet disposed on an upper portion of the fan guard for introducing the airflow into an interior of the fan guard, and an airflow outlet disposed on a lower portion of the fan guard for enabling the airflow to flow out of the fan guard and to the heat-generating device. In addition, the inner diameter of the airflow outlet is smaller than that of the airflow inlet, thereby concentrating the airflow flowing out of the airflow outlet toward the heat-generating device to dissipate heat generated from the heat-generating device. The fan guard further includes a plurality of ribs disposed in the airflow outlet of the fan guard and separating the airflow outlet into a plurality of isolated flow paths. There is a space formed between the ribs of the fan guard and the heat-generating device for enhancing the heat-dissipating efficiency. Besides, a radiator plate is mounted between the heat-generating device and the fan guard for transmitting the heat generated from the heat-generating device, wherein heat-generating device can be an electronic device. Accordingly, the heat generated from the heat-generating device can be dissipated by the airflow guided through the fan guard.
The present invention may best be understood through the following description with reference to the accompanying drawings, in which: